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Old 09-28-19, 09:11 AM   #6
AC_Hacker
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Quote:
Originally Posted by pinballlooking View Post
....They can be over sized and work very well in the bedrooms. In three bedrooms here two of them are over sized 9K units but the inverter units still works very well.
Yes, they will work well. But if the situation is such that if you can plan for it, slightly undersizing will be more power efficient.

Quote:
That COP is getting real close to GEO.
That is why it is so jaw-dropping. In this area, the COP exceeds previous GSHP units. The HSPF is based on a yearly average. And it's obvious that when outside temps go down, COP will also drop, the more "lifting" the unit has to do, the lower the COP.

I think that if the same attention was given to GSHPs as has been given to ASHPs, there would be big improvements there too. The physics of extracting heat from deep ground contact is absolutely better than extracting heat from ambient air. It's a matter of refinements, in my opinion

I'm fortunate to live in an area with fairly mild (low 40s to mid 30s), usually even winters. Which favors ASHPs. However, occasional dips, when an Alaskan cold front drops temps to low teens, for a few days, then the ASHPs are working hard.

-AC.
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